with a completely flat battery, will the door lock actuators failed as well?
my 1991 525i has some kind of power leakage recently (from somewhere i don't know) so the battery was drained and now the 4 door locks and unable to open even by the key! only the boot lid can be opened. how to open the door again without breaking the glass?
thank you.
Yes, nice huh? You can do the emergency unlock thing on the passenger door lock or you can pull the plate light and use that wire to power-up the system.
go here...
my keys (i got 2) can't even open the passenger door lock! i think i can locate the plate light but what do u mean by 'use that wire to power up the system'? do u mean making a short circuit?
thank you.
i think my procedures were a bit incorrect... i turn the key before i lift the door plate. anyway, i will try again and hope i can get into the car. thank you.
You need to remove the *trunk* light and hook up a slave battery to chassis and the live wire. This should send power to all the permanently powered things like the central locking. The license plate light is only powered if the lights are switched on.
However, there's a caution about this. If your battery is heavily discharged this might make more current flow from the slave battery to yours while it charges it than the wiring can handle - after all the boot light is only a few watts. So to be safe, I'd wire a 21 watt bulb in series with the connection. Leave it for a few minutes to charge the car battery slightly. Then with a bit of luck the central locking will operate.
Depending on model there you can mechanically unlock the driver (or LHS) door. Once you get into the car you can read how to do it in the manual ;-) A Google in the news groups should turn it up though.
Otherwise you can charge up the battery enough through the boot light, but do not over current or you will blow the battery supply fuse and then you will have to break a window.
thanks for all the input. i can now unlock the door using the emergency unlock method. the only thing left is to check if any electrical or electronic problem remains after a new battery is installed. once again, thank you.
I am currently -- as we speak -- playing with the door locks on my '94 E36, and I played with the trunk lock a few weeks ago.
I can say without reservation that the door locks are mechanical, and they work by the key on the door you are trying to lock or unlock. The other doors operate by electric motors, but the lock set with the key in it operates mechanically. When you use the key on ANY of the locks, that lock operates the latch directly -- unless it has other problems -- and this lock will work a switch that operats the rest of the locks on the car. Obviously, with a dead battery, the other locks will not operate in this way, but the door that you insert the key into will lock and unlock properly.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.